Multiple NIC's / Different subnets / Different subnet masks

[Brian Pedersen_1]

I have a HPUX 11.0 system running as a firewall. It has 4 NIC's in it. 3 of them are using registered IP address (3 different subnets) with 24 bit masks. The 4th interface is using a 10.240.0.0/16 IP address. It's address is 10.240.0.1. When I put a system on this interface at 10.240.10.1/16, it won't work, but it will if I change the IP to 10.240.10.2/16. It will also work on other host addresses within the 10.240.0.0/16 block. Any ideas?????

[Santosh Nair_1]

Are you sure that IP, 10.240.0.1 isn't already being used, i.e. duplicate IPs. The .1 address is commonly used for routers. What, if any errors are you getting?

-Santosh

[Brian Pedersen_1]

There aren't any dupl. IP's.. There are only 3 devices on that network, the firewall (10.240.0.1), the network switch (10.240.0.10), and the server (10.240.10.2). This is a new segment on the firewall and new network gear (and I installed it all, so I know there are no "extra" pieces of equipment) :-)

I'm not getting any errors, just no traffic gets there. The firewall can see/access the 10.240.10.1 address, but nothing else. I am running HP's Praesidium firewall software (formally Axent's Raptor firewall).... I've worked around it, but I don't like a "mystery" like this!!